Due to the emphasis of molecular biological approaches in the program project, we intend to establish a molecular biology core facility for use by research projects associated with the program project. One mission of the core facility will be to synthesize oligonucleotides to be used by various projects for PCR, site-directed mutagenesis, and DNA sequencing applications. In addition, core personnel will use site-directed mutagenesis to construct a library of CFTR CDNA constructs containing published, naturally occurring mutations. This library will be updated periodically and these constructs will be available to investigators to facilitate the analysis of mutations using the expression systems and analytical methods described in individual proposals. This will eliminate the redundancy that would result if each group prepared these constructs separately, and will also allow us to maintain greater quality control during the mutagenesis protocol. The facility will also carry out PCR applications, DNA sequencing, and Northern and Southern blots for investigators as needed.